According to a recent study by Oregon Health and Science University researchers, exercise appears to contribute to better blood-vessel development in the brain and to allowing a person to be more mentally alert.
It is commonly accepted that regular exercise has health benefits, including better cardiovascular health and a reduced risk of obesity. In addition, the brain chemicals released during exercise can ameliorate anxiety, stress, depression and frustration.
“While we already know that exercise is good for the heart and reduces the incidence of obesity, this study shows exercise can literally cause physical changes in the brain,” Dr. Judy Cameron of the Reproductive Sciences and Neuroscience at OHSU said. “Furthermore, we believe the study results show exercise causes a person to be more ‘engaged’ and provides another reason for Americans to make physical activity part of their daily regimen.”
In many people, exercise also produces a feeling of euphoria, which is the result of brain neurotransmitters and the release of endorphins.
University of Wisconsin professor of physiology Jerome Dempsey said that prior to this study, there was no documented evidence of a relationship between cognition and exercise.
“We used to think that exercise affected everything but the way you think,” Dempsey said. “This study may indicate that exercise does have an impact on cognition.”
The study involved 24 primates that were separated into three groups. The first group was a “running” group, which exercised on treadmills for a set distance five days a week for 20 weeks. The second group did not exercise during this 20-week period, and a third group exercised for 20 weeks and then remained sedentary.
Scientists measured the volume of small blood vessels, or capillaries, in the motor-cortex region of the brain in all three groups.
“What we found was a higher brain-capillary volume in those monkeys who exercised than in those monkeys who did not,” Cameron said. “The next step of this research is to determine whether other areas of the brain undergo physical changes. For instance, how are brain cells affected, and does that impact cognitive performance?”
Though Dempsey is enthusiastic about the study’s results, he said there is a definite need for further research.
“This is a very provocative finding,” Dempsey said. “But because it is not yet a peer-reviewed public paper, it could just be scientists boasting about their work.”
Dempsey also said he does not necessarily think capillary density is related to the benefits of exercise.
“The normal capillary density of the human brain is really something,” Dempsey said. “And the brain does not respond to exercise the same way that skeletal muscle does (with an increased amount of blood vessels). It is all pretty exciting, but there needs to be more research.”
A second aspect of the study evaluated mental performance and sought to determine if exercise affected cognitive function and mood in the primates. Scientists used a variety of methods, including evaluation of the primates’ ability to find a hidden treat.
“Tests showed that animals in the exercise group were more aroused, alert and engaged than animals in the control group,” Cameron said. “However, it’s important to note that both groups had essentially the same success rate. While more research needs to be done, this study did not demonstrate a relationship between exercise and increased cognitive function.”
